Statistical methods for the analysis and presentation of the results of bone marrow transplants. Part I: Unadjusted analysis

In this paper, we describe modern statistical methods for presentation of t he results of studies of bone marrow transplantation. We focus here on 'uni variate' or unadjusted techniques to describe the outcomes of such studies. In another paper we will discuss multivariate methods. We discuss the type of data one may have available to make inference about outcomes. We explai n the differences between the Kaplan-Meier estimator of the survival functi on and the cumulative incidence curve, how these curves should be interpret ed and when each is the appropriate summary statistic. We discuss the weigh ted log rank statistic and show how different weights can be used to put em phasis on detecting differences between groups in different time periods. W e also present a simple estimate of current leukemia-free survival which is useful in summarizing post-transplant events.